Question 173
MediumOriginal questionA tsunami is not one wave but a of waves, and it is caused not by the weather but by movement under the sea: an earthquake beneath the ocean floor, or an undersea volcano erupting.
Out in the deep ocean, a tsunami can be hard to notice. Its waves do not rise much higher than ordinary waves there. The danger comes as they travel towards land. As the water grows , the waves slow down and build up, higher and higher, until they strike the coast with terrible force.
Their speed depends on the depth of the water, not on how far they are from where they began. Over deep water, tsunami waves can travel as fast as a jet plane, slowing down only when they reach the shallows near the shore.
People often call a tsunami a "tidal wave", but scientists who study the ocean the name. , the regular daily rise and fall of the sea, have very little to do with these giant waves. Calling them tidal waves suggests a cause that is not the real one, and understanding the real cause matters to anyone who lives by the sea.
What does the speed of tsunami waves depend on?
Show the answer and explanation
Correct answer: A
Explanation
The third paragraph says "Their speed depends on the depth of the water, not on how far they are from where they began."
Worth noting
Distance from where the waves began is exactly what the passage says the speed does not depend on.
- Concept
- Reading a contrast carefully
- Typical timeTypical
- 40 s
- Your timeYours
- —
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